From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2D1A43A1AE; Mon, 18 Dec 2023 14:00:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="wMoXYKSV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A2E95C433C8; Mon, 18 Dec 2023 14:00:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1702908057; bh=VWC1jgiKJiLPuMiaSE41Q+RsR8v1Yw7kYeWZVjQzmpA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wMoXYKSVItIq2cKkUywAeOTF00bS+dGE09ckl9P2IATd4+z7T7Qdd07iVSpYPjOPw oM8iGy/yJD7OqzskgQmowjNq/WE7e69f+aJg99Xpur1Qolnq9k1I+YrLYpsCs1cQVQ L1ibv5pjgW38nrsVWdLbwUWlW9Pjtdza1retuPJg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Hyunwoo Kim , Paolo Abeni , Sasha Levin Subject: [PATCH 6.6 038/166] net/rose: Fix Use-After-Free in rose_ioctl Date: Mon, 18 Dec 2023 14:50:04 +0100 Message-ID: <20231218135106.690499763@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231218135104.927894164@linuxfoundation.org> References: <20231218135104.927894164@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hyunwoo Kim [ Upstream commit 810c38a369a0a0ce625b5c12169abce1dd9ccd53 ] Because rose_ioctl() accesses sk->sk_receive_queue without holding a sk->sk_receive_queue.lock, it can cause a race with rose_accept(). A use-after-free for skb occurs with the following flow. ``` rose_ioctl() -> skb_peek() rose_accept() -> skb_dequeue() -> kfree_skb() ``` Add sk->sk_receive_queue.lock to rose_ioctl() to fix this issue. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Hyunwoo Kim Link: https://lore.kernel.org/r/20231209100538.GA407321@v4bel-B760M-AORUS-ELITE-AX Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- net/rose/af_rose.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/rose/af_rose.c b/net/rose/af_rose.c index 49dafe9ac72f0..4a5c2dc8dd7a9 100644 --- a/net/rose/af_rose.c +++ b/net/rose/af_rose.c @@ -1315,9 +1315,11 @@ static int rose_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) case TIOCINQ: { struct sk_buff *skb; long amount = 0L; - /* These two are safe on a single CPU system as only user tasks fiddle here */ + + spin_lock_irq(&sk->sk_receive_queue.lock); if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL) amount = skb->len; + spin_unlock_irq(&sk->sk_receive_queue.lock); return put_user(amount, (unsigned int __user *) argp); } -- 2.43.0